Dinan only warrants consequent failures caused by the Dinan performance remap (let the arguments begin). For example, an auto tranny that appears to fail because of the significant increase in torque produced by the tune (let the arguments begin). The Dinan warranty mirrors the BMW as far as time/miles: 4yrs, 50k mi. I'm not familiar with other aftermarket tuners, but do any of them warrant consequent failures caused by their mods?